Process of making carbureted water gas



May 24, 1938. w. TIDDY 2,118,332

PROCESS OF MAKING CARBURETED WATER GAS Original Filed June 5, 1931607cm: for

- I INVENTOR 1447/94/77 7/2/4 ATTORNEY Patented May 24, 1938 WilliamTiddy, New York, N. Y., assignor to Scmet-Solvay EngineeringCorporation,

New

York, N. Y., a corporation of New York Original application June 5,1931, Serial No.

542,287, now Patent No. 2,064,007, dated Decemher 15, 1936. Divided andthis application May 23, 1936, Serial No. 81,413

1 Claim.

This invention is directed to a processfor making carbureted water gasand more particularly to the operation of a carbureted water gas setinvolving a generator, carburetor and super- 5 heater, connected inseries. This application is a division of my co-pendlng applicationSerial No. 542,287 filed June 5, 1931, now Patent No. 2,064,007.

One object of this invention is to provide a process of making water gasin which Bunker C or other crude or heavy oils may be' efliciently usedto carburet the water gas. Other objects and advantages of thisinvention will appear from the following description thereof.

Heretofore, the usual water gas set consisted of a generator containinga bed of fuel, a carburetor, and a superheater, connected in series, thetop of the generator communicating with the top of the carburetor, andthe base of the superheater. The interiors of both the carburetor andsuperheater were built up with checkerbrick arranged in staggeredrelation to form tortuous flues. In the manufacture of water gas,

25 the blast gases produced in the generator by the passage of air orother oxygen-containing gas through the fuel bed therein were passedfrom the generator into and through the carburetor and superheater.Secondary air admitted to the 30 carburetor and the superheater wasadmixed with the blast gases and this mixture ignited in its passageover the checkerbrick and burned in these chambers, thus heating. thecheckerbrick. Thereafter, the blasting cycle was discontinued 35 andsteam admitted into the generator, passing therethrough, reacting withthe fuel bed to form water gas, which was passed into the carburetor.011 was introduced into the top of the carburetor, the resultant oil gasmixing with the water gas 0 in passing over the checkerbrick therein.The mixture of oil gas and water gas, in its passage through thecarburetor and superheater chambers was fixed to form carbureted watergas. If desired, steam was thereafter passed in reverse flow through thesuperheater and carburetor units down through the fuel bed in thegenerator, the resultant water gas being withdrawn directly from thebase of the generator. When the tem- 59 peratures of the fuel bed andthe carburetor and superheater chambers had been reduced so that watergas could no longer be efflciently generated, the gas making cycles werediscontinued and the fuel bed again blasted with air or other 66 oxygencontaining gas and upon completionof (Cl. 48-205) I this blasting cycle,the water gas making cycles were repeated.

It has been proposed to substitute for the usual enriching oil, whichdoes not form. substantial carbonaceous deposits on the checkerbrick,

crudes, or unrefined oils. In practice, however, it has been found thatsuch oils leave an increased carbonaceous deposit on the checkerbrick inthe carburetor, clogging the fiues and necessitating frequent shutdownsfor rccheckering. The arrangement of checkerwork in the carburetorprecludes the cleaning thereof without removal of the checkerbrick fromthe carburetor chamber and consequently the entire checkerwork had to bereplaced, thus entailing arduous and time-consuming labor and reducingthe gasmaking capacity of the plant, since the carburetor had to betaken out of operation for a considerable period of time.

In accordance with Doherty Patent No. 992,944, of May 23, 1911, theamount of checkerbrick in the carburetor of a water gas set has beenreduced and the carbureting oil has been introduced into an unobstructedspace at the top of the car- 7 buretor, into the downwardly flowingwater gas stream, so as to obtain substantially complete volatilizationof the oil before it contacts with hot checkerbrick to thereby reduce oreliminate the formation of carbonaceous deposits. Further, in view ofthe clogging of the checkerbrick when using crude oils, it has beenproposed to omit the checkerbrick in the carburetor and introduce crudeoil as the enriching medium into the top thereof, the oil gas and watergas flowing in the same direction down through the carburetor into thebase of the superheater and up therethrough.

In contradistinction to the above operations, the carbureted water gasset in which the process of this invention is carried out involves ageneratorcontaining a bed of fuel, a carburetor, and a superheater.Preferably, each unit is contained in a separate and detached shell. Theseparate shells are connected in series with the top of the generatorcommunicating with the base of the carburetor and the top of thecarburetor communicating with the base of the superheater. An oiftakeleads from the top of the superheater to a washbox or seal and anofitake, separate from and independent of the connection between thegenerator and carburetor, leads from the base of the generator to awashbox or seal, which may be the same washbox into which the oiftakefrom the superheater leads. The interior of the superheater may be builtup with checkerbrick defining known in this art. I

In accordance with this invention; the base portion of the carburetor isdevoid of checkerbrick and substantially unobstructed throughout itsmajor portion. At a point in the carburetor approximately one-third thedistance from the top, arches are built which support checkerworkdefining tortuous flues in the topportion of the carburetor. Gas oils,Bunker C or crude oils are introduced into the carburetor at pointscircumferentially of this shell inthe neighborhood of the arches. Theoil is directed downwardly into 7 the upflowng water gas stream. Due tothe high temperatures prevailing in the neighborhood of the arches, asmore fully explained hereinafter, the oil is cracked and volatilizedsubstantially immediately as it enters the carburetor, the oil gasmixing with the water gas and the mixture passing through thecheckerbrick in the top of the carburetor and is thus partially fixedbefore it is introduced into the superheater. The car-, bonaceousresidue formed during the cracking of the crude oil settles to the baseof the carburetor, passing counter-current to the flow of water gastherethrough so that substantially all residual volatiles are removedtherefrom. The residue collects at the base of the carburetor during thewater gas making cycle, where it does not interfere with the gas flowthrough the carburetor. During the succeeding blasting cycle, this hotresidue serves to initiate the ignition of the mixture of blast gasesand secondary air. Further, it is partially burned by the passagethereover of the hot blast gases admixed with secondary air, thusretarding accumulation thereof. When the residue accumulates to such anextent that it impedes flow, the major portion thereof is withdrawnthroughclean-out doors provided in the carburetor for this purpose.

In the accompanying drawing, forming a part of this specification andshowing, for the purpose of exemplification, a preferred form of thisin-' ,vention, without limiting the claimed invention to suchillustrative instance, the single figure is a side elevation, partly insection, of a carbureted water gas set illustrating a preferredembodiment of this invention.

Referring to the drawing, numeral l0 indicates a generator containing abed of fuel (not shown). As customary, the top of the generator isprovided with a charging opening H for fuel. Air or otheroxygen-containing gas for blasting the fuel bed may be supplied throughpipe l2 having one end communicating with an air blower or pump andprovided with a conduit [3, leading into the generator below the gratesupporting the fuel bed. A valve controlled pipe I 4 leads into the baseof the generator, and a valve controlled pipe 15 into the top of thegenerator above the fuel bed to supply steam for uprun and downrun"water gas making cycles respectively.

Conduit I 6 communicably connects the top of generator ill with the baseof the carburetor ii. A dust catcher I 8 is associated with angle bend[9 inconduit IE to receive coal or dust particles separating out fromthe gas due to the bafliing action caused by the change in direction offlow of gas from the top of the generator through conduit l6 into thebase of the carburetor i1. Pipe 20 communicates with the main l2 toprovide secondary air or other oxygen-containing gas to the carburetorIT. The major portion of carburetor II, from the base up, as indicatedby the reference numeral 2|, is unobstructed. At the tortuous flues forthe passage of gas as is well top of the unobstructed portion 2|,refractory arches 22 disposed diametrically from one side of thecarburetor to the other, bind with the refractory lining of thecarburetor. Checkerbrick 23 of a type usually employed in thecarburetors of water gas sets rests on the arches 22 and definestortuousflues for the passage of gas. Checkerbrick 23 extends from thearches 22 to a point somewhat below the top outlet 24.

Gas oils or Bunker C oil are introduced into the carburetor through oilsprays 25 disposed circumferentially about the carburetor shell atpoints in the neighborhood of and below the arches 22. Oil sprays 25 arepreferably downwardly directed so that the oil is introduced in adirection counter-current to the upfiow of water gas through thecarburetor. Due to the high temperatures prevailing in the neighborhoodof arches 22, the oil is substantially instantaneously cracked andvaporized, the resultant oil vapors commingling with the water gas andthe resulting mixture passing through checkers 23. Downward introductionof oil through a series of spaced sprays into the upwardly flowing watergas causes agitation of the water gas-and eflicient admixture of watergas with oil gas, thus resulting in an improved mixture of oil gas withwater gas and increasing the oil efflciencies of the process,particularly as compared with prior practice,involving co-current flowof water gas and oil introduced into the carburetor. The carbonaceousresidue formed in the oil cracking settles through the unobstructedportion 2| of the carburetor and is contacted with hot water gas in itspassage down through the carburetor. This results in the removal of anyresidual volatiles in the residue. The residue accumulates on the baseof carburetor I! where it does not inter fere with flow of water gasthrough the carburetor. When suflicient residue has accumulated on thebase of the carburetor, it is withdrawn through a clean-out door (notshown) provided at the base of the carburetor for this purpose.

Conduit 26 connects the top outlet 24 of carburetor H with the base ofthe superheater 21, the interior of which is preferably of usualcheckerbrick construction. Tertiary air or other oxygencontaining gasmay be admitted to the base of superheater 21 through pipe 28, whichextends from pipe i2 and leads into the conduit 26. Steam for backrunwater gas making cycles may be supplied to the top of superheater 21through valve controlled steam pipe 29. As customary, the topofsuperheater 21 is equipped with a valve controlled blast offtake 3|and a water gas olftake 32 leading from the 'top of the superheater to ahousing 33. A backrun pipe or ofitake 34 leads from the base ofgenerator l0 into housing 33. Flow through conduits 32 and 34 iscontrolled by a single valve positioned in housing 33 and arranged toopen conduit 32, permitting flow of gas therethrough and simultaneouslyclose conduit 34 preventing flow of gas therethrough and vice versa, asmore fully disclosed in Patent No. 1,605,081, granted November 2, 1926.

Housing 33 communicates with a washbox or seal 35 through conduit 35. Agas offtake 31 leads from the washbox 35.

The operation of the above described set may comprise three cycles inany desiredorder; to wit: blasting, uprun, and backrun cycles. Duringthe blasting cycle, air or other oxygencontaining gas is passed into thegenerator through air main l3, up through the fuel bed therein, reactingtherewith to form blast gases 7 and raising the temperature thereofuntil the bed of fuel becomes" an incandescent mass. The resultant blastgases are passed from the generator l through conduit l6 into thecarburetor 2|, and

up therethrough. Secondary air is admitted to the carburetor throughpipe 20. The mixture of air and blast gases heats the base portion ofthe carburetor, ignition of the mixture being initiated by contact withthe hot carbonaceous residue accumulated at the base of the carburetors.This residue is burned by the passage of blast gases admixed withsecondary air thereover. Arches 22 and checkerbrick 23 serve aslargereservoirs of heat, and cause the complete ignition and burning ofthe blast gases admixed with secondary air. As a result, the arches 22and checkerbrick 23 become highly heated because of the combustion ofthe mixture of blast gases and air in contact therewith during itspassage through the carburetor. Radiation and conduction of heat fromthe arches 22 and the checkerbrick 23, resting thereon, result in thehighest temperatures in the carburetor prevailing in the neighborhood ofthe arches. The gases from the carburetor are passed through conduit 26where they may be mixed with tertiary air entering at 23, thence intoand through superheater 21, where combustion of the gases is completed.The waste gases leave the superheater through valve controlled stack 3|.

Upon completion of this blasting cycle, which may last approximatelythree minutes, valve 3| is closed and the valve controlling the flow ofair through passage I2 is also closed. An uprun cycle may then be begun.Steam is passed into the base of. the generator through inlet I4 and thevalve in housing 33, positioned to permit flow through conduit 32, intowashbox 35, and prevent flow through conduit 34 into the washbox. Thesteam admitted at M passes up through the fuel bed, reacting therewith,to form water gas, which passes from the generator through conduit l6into the unobstructed portion of carburetor Gas or crude oil isdischarged into the carburetor through oil sprays 25. The hightemperatures prevailing at the point of introduction of the crude oilcauses eflicient volatilization and cracking of the oil with theproduction of carbonaceous material and oil gas. Introducing the oil ina counter-current direction to the flow of water gas through thecarburetor results in improved dispersion and admixture of the oilparticles and resultant vapors with the water gas. The oil gas formed bythe vaporization of the oil particles becomes intimately mixed with thewater gas by reason of the agitation of the two fluids within thecarburetor, resulting from the counter-flow. carbonaceous residue formedby the cracking of the oil settles down through the large unobstructedportion 2|, countercurrent to the flow of water gas -therethrough. Theresidue accumulates at the base of the carburetor during the water gasmaking cycles, where it does not interfere with the flow of gas throughthe carburetor. During the subsequent blasting cycle, as indicatedabove, the residue is partially consumed by the passage of blast gasesand secondary air thereover. Consequently, the removal of the residue isrequired only at infrequent times. Passage of the mixture of oil gas andwater gas over the checkerbrick 23 results in partial fixing of themixture of oil gas and water gas prior to the introduction of themixture into the superheater. The resultant mixture passes from thecarburetor, through conduit 26, into the superheater 21,

where fixation is completed, From the superheater, the carbureted water'gas formed passes into the washbox 35, from which it is dischargedthrough outlet 31 into a suitable holder.

The uprun period may be followed by a backrun. Conduit 34 is opened and32 closed by means of the valve in housing 33 and steam is shut offthrough inlet l4 and turned on at inlet 29. The steam admitted at 28 issuperheated in its passage through the superheater and carburetor andthen passes into the top of the generator downwardly through the fuelbed therein, the resultant water gas being withdrawn from the generatorthrough conduit 34. If desired, crude oil or other enriching medium maybe added through 011 sprays 25 and the mixture of superheated steam andoil gas passed through pipe l6, down through the fuel bed in thegenerator, the resultant carbureted water gas being withdrawn directlyfrom the generator through pipe 34. In lieu of, or in addition to, thecomplete backrun cycle above described, a partial backrun cycle may beconducted in the set. For this purpose, steam is introduced at I5,passed down through the generator, the resultant water gas beingwithdrawn directly from the base of the generator through the backrunpipe 34.

It will be noted that in the process of this invention water gas from anoutside source is caused to flow in an extended vertical unobstructedpath through the carburetor, and upon leaving the unobstructed pathcontinues to flow in the same vertical direction through thecheckerbrick 23 at the top of the carburetor and then flows up throughthe superheater. Heavy oil is introduced peripherally into thisunobstructed path of flow at the top thereof through a plurality ofsprays inclined downwardly so that the atomized oil is projected in aplurality of streams the carbureted water gas thus produced being fixedas it flows vertically over the checkerbrick 23 in the carburetor andthat in the superheater. Solid carbonaceous residue formed upondecomposition of the oil settles through the upwardly flowing water gasstreamand in its passage through the extended vertical path in contactwith the water gas any residual oil adhering thereto is vaporized. Thecarbonaceous material collects on the bottom of the carburetor, where itserves the useful function of igniting the air and blast gasesimmediately as they enter the carburetor during the blasting cycle. thecarbonaceous deposits may be burned during the blasting cycle,combustion thereof being supported by secondary air admitted throughpipe 20 and the heat thus generated stored in the carburetor.

I claim:

In a process for producing carbureted water gas in a set involving asingle generator containing a bed of fuel of coal origin connected tothe base of a single carburetor having the major portion thereofsubstantially unobstructed throughout the horizontal cross-sectionalarea thereof, said process comprising alternately preheating saidcarburetor by air blasting the said bed of fuel in the generator andpassing the resultant blast gases upwardly through the carburetor in aMoreover,

flowing stream of water gas counter-current to the flow thereof wherebyturbulence between the oil and water gas is produced and eflectivevaporization and cracking of the oil takes place causing the resultantcarbonaceous deposits to settle through the upwardly flowing water gasstream so as to eflectively vaporize any residual oil adhering theretoand repeating the aforesaid steps utilizing as the fuel bed only thesaid bed of fuel of coal origin, which is replenished m from time totime.

WILLIAM TIDDY.

